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The following are some more thoughts and information about Chevy V-8 small and big block
engines. They're in no particular order and can be browsed at your leisure. If you
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Don't forget to BOOKMARK this page or add it to your "FAVORITE" pages. If you are running a website feel free to add this page to your "LINKS" page. Make sure that the distributor you use actually has a working ignition curve. A number of times I've seen someone buy a new or rebuilt motor and then use a 20 or 30 year old distributor from the original engine. Sometimes the new motor runs poorly and sometimes the problem can be traced to the fact that the ignition advance mechanism in the distributor no longer works. A vacuum advance canister may be worn out or the ignition advance weights and springs may be worn, the distributor shaft may be worn out and wobbling or the stop pins or pin bushings can be broken or worn. Make sure you check and test the distributor advance to see if it works. Recurving of the advance may be necessary depending on the type of engine and vehicle use. Big block oval port cast iron heads were made in two different configurations. The large oval port heads found on many passenger vehicles and trucks and the small oval port heads (which are also sometimes called peanut ports or round ports or truck ports) found on many big block 454 truck engines made after '76. Each of the oval port head sizes used a matching intake manifold. If you are building a motor for pulling or towing on the street, the small oval port heads will make their power at low and mid range rpms, but run out of breath at rpms over 4500. If you are building a strong street performer or a bracket racer, the large oval port heads are the ticket up to about 6500 rpm if you do some bowl porting and add the 2.19"/1.88" valves. Some of the better performing cast iron large oval port castings are the open chamber designs like the "781" or "049" casting. You can get an aluminum version of the large oval port, open chamber head under casting number "391" from GM/Performance Parts. |
The Gen.V and Gen.VI crankshafts for the 454 and 502 motors share a 4" stroke and a one -piece rear main oil seal, however, they are not balanced the same. The steel Gen.V 454 crank is PN-14096983, while the steel 502 crank is PN-10183723. Both are externally balanced. The Mark IV 454 and 502 "1053" steel cranks, for use with two-piece rear main seals, is PN-3963523. A forged "5140" Mark IV 454/502 4" stroke crank is found under PN-3963524. If you are looking for a 3.76" stroke forged crank to use in a '91 or later Gen.V or VI block with a one-piece rear main seal, you can use PN-10114186. This crank came in Gen.V/VI 427 tall deck truck blocks.
Keep in mind that the Gen.V/VI big block production motors made from '91 thru the present have non-adjustable valvetrains. If you want to convert them to adjustable valvetrains use the guideplates, pushrods, rocker arms, rocker arm studs, balls and nuts from a Mark IV setup. The Gen.V/VI valvetrains use a rocker arm bolt (instead of a stud) that has a 3/8" diameter thread going into the head. You will have to drill and tap the Gen.V/VI head to accept the Mark IV rocker arm stud. The Mark IV uses a 7/16" thread stud. The Gen.V/VI production rocker arm is different from the Mark IV and is not interchangeable with Mark IV rocker arms.
Do you have a tired later model '85-'92 305 smallblock with the TPI? Want to move up to a 350 shortblock and use your TPI induction? No problem. Just change the 305 injectors to the higher capacity 350 (22 lbs./hour) injectors and switch to a 350 style chip in the computer. An alternative is to replace the stock, non-adjustable fuel pressure regulator with an aftermarket "adjustable" regulator, turn up the fuel pressure to 50 psi and use the 305 injectors. Make sure you use an electric fuel pump and a fuel filter that can provide the increased fuel pressure and volume required. This assumes you are running the stock cam, heads and other engine internals.
Nominal production block deck heights on small block V-8's is 9.025". The production big blocks have deck heights of 9.8", while the tall deck truck 366T and 427T big blocks have deck heights of 10.2". Bowtie big blocks are available in "short" or "tall" deck versions.
Before you initially fire up that new or newly rebuilt engine make sure you "pre-lube" it. You can buy a number of different, inexpensive tools to do this. Turn these priming tools with a 1/2" electric drill and keep turning until you can see oil coming out of all of the rocker arm oil holes. It may take a few minutes. You can also turn the crank over by hand to move the crank oil distribution holes around to different positions and to make sure that oil has replaced all of the air in the oiling passages throughout the engine. You can also make a priming tool out of an old point style distributor. Remove the rotor, mechanical advance weights and springs and the top plate on the shaft. Then remove the points plate. Grind off the teeth on the bottom drive gear of the distributor.
RWD TRANSMISSION GEAR RATIOS:
AUTOMATIC:ALLISON 1000 - 3.10 - 1.81 - 1.41 - 1.00 - 0.71 POWERGLIDE - 1.82 - 1.00 1.76 - 1.00 TURBO 200-R4 - 2.74 - 1.57 - 1.00 - 0.67 TURBO 4L60 - 3.06 - 1.62 - 1.00 - 0.70 TURBO 4L60E - 3.06 - 1.62 - 1.00 - 0.70 TURBO 4L60E - 3.06 - 1.75 - 1.00 - 0.70 TURBO 4L65E - 3.06 - 1.62 - 1.00 - 0.70 TURBO 4L80 - 2.48 - 1.48 - 1.00 - 0.75 TURBO 4L80E - 2.48 - 1.48 - 1.00 - 0.75 TURBO 4L85E - 2.48 - 1.48 - 1.00 - 0.75 TURBO 350 - 2.52 - 1.52 - 1.00 TURBO 400 - 2.48 - 1.48 - 1.00 TURBO 700-R4 - 3.06 - 1.62 - 1.00 - 0.70
MANUAL:
BORG WARNER T10- 2.23 - 1.76 - 1.30 - 1.00 2.43 - 1.64 - 1.24 - 1.00 2.64 - 1.76 - 1.35 - 1.00 2.64 - 1.64 - 1.24 - 1.00 2.88 - 1.76 - 1.35 - 1.00 2.88 - 1.91 - 1.35 - 1.00 3.42 - 2.28 - 1.46 - 1.00 3.44 - 2.28 - 1.46 - 1.00 BORG WARNER T5 - 2.95 - 1.94 - 1.34 - 1.00 - 0.63 (TBI) 2.75 - 1.94 - 1.34 - 1.00 - 0.74 (TPI) BORG WARNER T56- 2.66 - 1.78 - 1.30 - 1.00 - 0.74 - 0.50 2.97 - 1.94 - 1.35 - 1.00 - 0.84 - 0.62 3.36 - 2.07 - 1.35 - 1.00 - 0.84 - 0.62 2.97 - 2.07 - 1.43 - 1.00 - 0.84 - 0.57, GTO, CTS-V 2.29 - 1.61 - 1.27 - 1.00 - 0.85 - 0.75, C5 Corvette MUNCIE M20 - 2.56 - 1.91 - 1.48 - 1.00 2.52 - 1.88 - 1.46 - 1.00 MUNCIE M21 - 2.20 - 1.64 - 1.28 - 1.00 MUNCIE M22 - 2.20 - 1.64 - 1.28 - 1.00 SAGINAW (4spd.)- 3.11 - 2.20 - 1.47 - 1.00 2.85 - 2.02 - 1.35 - 1.00 2.54 - 1.80 - 1.32 - 1.00 2.54 - 1.80 - 1.44 - 1.00 ZF6 3.07 - 1.80 - 1.43 - 1.00 - 0.71 - 0.59 ZF S6-650 5.79 - 3.31 - 2.10 - 1.31 - 1.00 - 0.76
Big block Chevys have used three different pushrod diameters over the years. The pushrod diameters are 5/16", 3/8" and over the counter heavy duty 7/16". Each pushrod has a matching pushrod guideplate. Production motors with low lift cams have used the 5/16" pushrod and matching guideplate. Early production Mark IV big blocks used a 3/8" diameter with higher lift production camshafts. Gen.V and VI production big block use a 3/8" pushrod and matching Gen.V/VI guideplate. The 7/16" is strictly for racing and very high lift cams and high valve spring open pressures.
The standard production lengths for Mark IV big block pushrods, with flat tappet cams, is 8.285" for the intake and 9.256" on the exhaust. The Gen.V production engines with non-adjustable valvetrains use shorter pushrods that measure 8.171" intake and 9.151" exhaust.
Pushrods used on the production 366T and 427T "tall" deck motors are .400" longer to make up the difference in block deck height.
GM/PERFORMANCE PARTS
HOLLEY CARB INFORMATION
CHEVY V-8 CASTING NUMBER LOCATIONS
CHEVY V-8 CRANKSHAFT JOURNAL SIZES
CHEVY V-8 CRANKSHAFT CASTING NUMBERS
HOT LINKS
CHEVY V-8 BORE AND STROKE LIST
CHEVY ENGINES AND PARTS ON EBAY
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